Prime will not remove ammonia, but detoxifies it. I would suggest water changes to help lower the ammonia and treat the new water with prime.
I try to keep ammonia and nitrites under .25 ppm when doing a cycle with fish. It can be a lot of hard work, water changes one or two times a day.
What type of fish are in the tank? A 50-75% water change would be a good start, with ammonia being that high.

Plus, add a biological supplement to jumpstart the bacteria. Seachem's Stability and Nutrafin's Cycle are two I've used. A better one is the Bio... something that Dr. Tim Hovanec developed, if memory serves me correctly; you can get it in the US [can't in Canada because it is frozen bacteria and they won't allow it across the border, so I've never used it, but I hear it is good]. These things work by adding bacteria (somehow) that immediately begin consuming the ammonia and then the nitrite to cycle the tank, provided the fish load is not beyond its capabilities. Or you can seed bacteria from an established tank.

The aquarist is one who must learn the ways of the biologist, the chemist, and the veterinarian.[unknown source]

Something we all need to remember: The fish you've acquired was quite happy not being owned by you, minding its own business. If you’re going to take it under your wing then you’re responsible for it. Every aspect of its life is under your control, from water quality and temperature to swimming space. [Nathan Hill in PFK]

To add to what Byron said: The product he is talking about is Bio-Spira and it's not cheap. I used it on the initial set up of my display tank and it dramatically decreased my cycling time. The problem with it, other than the expense, is not knowing if it's been shipped properly. If at any time it was allowed to defrost during transit (there is no way to know this) the bacteria will have been rendered useless. Another product I have used and was happy with was Tropical Science's Nitromax.